At Fluidinfo we chose Twisted as the basis of all internal networking for our
distributed, shared, always-writable database, FluidDB. We threw out
a year's worth of working, debugged, tested C code in order to move to Twisted. As
I often tell people, we're using Python because of Twisted, not the other
way round. I'm an unabashed Twisted fanboy. In particular,
Twisted's Deferreds are one of the most elegant and flexible
programming constructs I've ever worked with.
Plus, the Twisted community is great - not only the core developers,
but also the 180+ people constantly in #twisted in IRC.

Canonical has been using Twisted as key part of Launchpad.net for over
five years now. We use Twisted to run our SSH servers, our process
pools, our package build farms, our file storage system and many other
things. Practically every time we need to glue two systems together,
we use Twisted. When we don't, we regret it later.

Justin.tv is the largest live video site on the internet. We allow anyone to broadcast live video from their PC and chat with viewers. Every second of every broadcast is archived so it can later be browsed, searched, or made into highlight clips.

We developed custom Flash video software, the Python Media Server, which uses Twisted as the event framework. We were able to set the record for the highest number of simultaneous viewers (over 400,000) for a live video site. Our Twisted video cluster currently supports thousands of simultaneous broadcasts and serves up to 30M live video streams per day.

TweetDeck aims to build a browser for the
real-time web. Right now we're the biggest Twitter client after the
website itself, and are rolling out full integration with Facebook and
other services. With TweetDeck you can organize real-time streams of
information into a convenient grid format that allows easy digestion.

We use Twisted to power our backend services, specifically our new
accounts system and sync functionality we introduced recently
(​http://tweetdeck.com/beta/features/take-tweetdeck-with-you/). We've
deployed our Twisted services over the Amazon cloud - specifically, we
use EC2 and SimpleDB. Writing a REST api service used by hundreds of
thousands active users was a snap with Twisted. We'll continue to use
Twisted as we broaden our server-side processing goals.

I wanted to test out some news/mail gatewaying for Mailman 2.1 but I didn't want to go through the hassle of actually connecting things up to a real news server, and I definitely didn't want to actually try to install inn or some nonsense (I'd like to do some other work this week :).

I wished I had something like Lib/smtpd.py in the Python distro for the server side of NNTP, then it dawned on me that I remember Moshe and crew saying that Twisted comes with a news server. Well, let's just see how easy it would be to hook up.

You guys have a big problem, because it was way too easy to do! How are you going to make the big consulting bucks? :)

Three commands and I had an nntp server with a single newsgroup that was featured enough to connect Mozilla to, and to point Mailman's gateway at and actually get messages flowing back and forth. Congratulations!

-- Barry Warsaw

NASA

My team is developing a modular application to integrate CAD/CAE/CAM tools and data and to enable collaboration among distributed teams of engineers working on NASA projects. We have selected Twisted as our framework because of its pluggable, asynchronous protocols, support for multiple interfaces and protocols per service, integration with PostgreSQL, and just generally excellent layered architecture.

-- Stephen C. Waterbury, NASA

PowerCard

PowerCard is the software platform we developed for
​PowerCard Rewards and the Original Rewards program for ​Original Restaurants. Original Restaurants promotes unique, local restaurants by providing cooperative marketing, customer sharing, and a distinctive Rewards Card program.

We use Twisted extensively for back-end transaction services for the loyalty rewards and gift card programs. We also used Twisted in our client-side applications installed in demanding restaurant environments. Twisted was crucial in our ability to craft solutions to interoperate with multiple restaurant POS vendors (Micros, Aloha/Radiant, Squirrel,
etc.), each with differing protocols and access methods. Our choice of Python and Twisted allows us to rather easily extend our system to support new features and requests with limited amount of developer time and budget.

Key features for us:

Easy implementation of custom and existing network protocols

Consistent APIs for code sharing between client and server implementations

Thusa is a solution provider for many businesses in South Africa. This requires tracking and maintenance of many Linux based servers deployed in a wide range of locations.

Twisted has enabled Thusa to build a wide range of applications to ease this task and improve efficiency both for Thusa and its customers. From distributed package management and security auditing of all servers deployed in the field, to simplified LDAP tree management. Thanks to the multi protocol capabilities of Twisted and Nevow, creating web interfaces for otherwise complex applications becomes trivial.

Botonomy LLC is a small software firm in the Philadelphia area. We help small teams solve large problems.

Our first application, ​ProjectPipe, is a hosted project management solution that provides midsize teams with everything that they need to manage IT projects. We have built our hosted application infrastructure atop Twisted, Nevow, PostgreSQL, and Jabber/XMPP. Twisted's multi-protocol support has been one of the key enablers of the unique technical architecture that we employ in our product offerings.

The core Twisted development team consistently demonstrates a strong commitment to delivering robust, high quality software. Twisted's documentation is accurate and concise, and the expertise and helpfulness of the larger developer community is second-to-none.

When evaluating the technologies on which you are staking your business, you need to evaluate both the code and the community that surrounds it. Twisted passes with flying colors in both regards.

At Reflexions Data, we provide custom development services for a wide variety of clients. We recently completed work on a project for a new client; the timeframe available required us to expedite every step of the development process. Twisted allowed us to quickly implement a custom client/server protocol with a wide variety of extra functionality for free.

The quality of the Twisted networking core is unmatched in the open- or closed-source arenas. Due largely to its asynchronous networking model, we were able to ensure our clients scalability needs would be met.

Our experiences with the Twisted developer community were top- notch; the turnaround time on questions posted to the developer mailing list was simply amazing. We were so pleased with the results of our first professional use of the Twisted core that we plan on investigating how we can make use of the other facets of the Twisted project.

At Masters of Branding we use Twisted as the networking core for all of our client and server RFID software. It was by far the easiest framework to develop with, debug under, and extend for our purposes to support protocols such as SOAP, HTTP, and Macromedia Flash-compatible XML Sockets. The API and event model are both very well thought out and has accommodated all of our networking needs from database-heavy server software on Linux to (py)OpenGL visualization applications on win32.

The ease and power of Python and Twisted really showed through when we took one of our applications developed in and for Linux and ported it to run as a Windows NT service in less than day. New users to the framework will not only be impressed by the power of the software, but also that the developer/user community responsible for it are incredibly helpful and often provide much better support in minutes or hours than you'll see from commercial shops given days or weeks.

We discovered Twisted 10 months ago, and now it is a key element of our development strategy. We have successfully used Twisted on several projects, of very different problem domains.

We developed a highly scalable realtime application for customer support, which serves web-based clients as well as clients implemented in any of the many protocols supported by Twisted. Twisted was also used to develop targeted proxies for various applications supporting more than 15.000 users. Twisted handles the charge with no problem.

We intend to continue using Twisted on upcoming projects, especially since integrated support for databases and new services are being added very quickly.

We found Twisted to be powerful, comprehensible, well documented, and backed by a good helpful community. We'll use it on our next products for sure!

-- Luc Stepniewski, Head Engineer, Adelux, France

MC-Foo and Ldaptor

I was writing ​MC Foo, a networked multiuser learning Ogg/MP3 jukebox application, in C, and was frustrated about the amount of time it took to debug. I decided I should use a higher-level language. I liked how Python felt, but had never written a single line of Python. I decided it was time to learn. Five hours later, the core of my application was rewritten in Python, using Twisted for main loop and networking. Another five hours later, I had replaced my oversimplistic line-based protocols with PB, the Twisted RPC protocol. Twisted has also enabled me to easily add features such as implicit persistence into MC Foo. And it even has nice GUI integration, allowing one to do sane networking in a GUI application.

Since then, I have created ​Ldaptor, a pure-Python LDAP library, utilities and a web interface, as a data structure library, Twisted protocol and Twisted applications. The way how the web interface plugs in with the LDAP protocol handling still manages to amaze me.

The developer community behind Twisted is just great, and the IRC channel is a great source of information. All in all, I feel Twisted is one of the most interesting projects on the net.